.TH SNIP 1 "1 December 2013" "WFDB 10.5.21" "WFDB Applications Guide"
.SH NAME
snip \- copy an excerpt of a WFDB record
.SH SYNOPSIS
\fBsnip -i\fR \fIinput-record\fR \fB-n\fR \fInew-record\fR [ \fIoptions\fR ]
.SH DESCRIPTION
\fBsnip\fR copies the signal files (and, optionally, annotation files) of
the specified \fIinput-record\fR, and generates a header file, thereby creating
the specified \fInew-record\fR.  \fBsnip\fR is usually used to extract an
excerpt of its \fIinput-record\fR, using the \fB-f\fR and \fB-t\fR options (see
below) to specify the segment to be copied.
.PP
The program \fBxform\fR(1) can also perform this task, but offers additional
flexibility (it can scale the signals, resample them at a different frequency,
rearrange them, select subsets of them, or reformat them);  \fBsnip\fR is
faster than \fBxform\fR, however.
.PP
\fIOptions\fR are:
.TP
\fB-a\fR \fIannotator\fR
Copy the specified \fIannotator\fR as well as the signal files.  Two or more
\fIannotator\fR arguments, separated by spaces, can follow \fB-a\fR.  An
annotator supplied via the standard input may be specified using `\fB-\fR', but
only immediately after \fB-a\fR;  in this case only, annotations are copied
to the standard output.
.TP
\fB-f\fR \fItime\fR
Begin at the specified \fItime\fR in the input record (default: the
beginning of the record).
.TP
\fB-h\fR
Print a usage summary.
.TP
\fB-l\fR \fIduration\fR
Snip a segment of the specified \fIduration\fR (hh:mm:ss or s\fInnnn\fR;
overrides \fB-t\fR if given).
.TP
\fB-m\fR
Preserve segments of multi-segment input, if possible.
.TP
\fB-O\fR \fIformat\fR
Write output in the specified \fIformat\fR.  See \fBheader\fR(5) for a list of
available formats (16, 80, 212, ...).  If this option is omitted, \fBsnip\fR
uses a format that best fits the ADC resolution of the samples.
.TP
\fB-s\fR
Suppress output of info strings in the output header file.
.TP
\fB-t\fR \fItime\fR
Process until the specified \fItime\fR in the input record (default: continue
to the end of the record).
.SH ENVIRONMENT
.PP
It may be necessary to set and export the shell variable \fBWFDB\fR (see
\fBsetwfdb\fR(1)).
.SH FILES
.TP 22
\fInew-record.annotator\fR
output annotation file
.TP
\fInew-record\fR.dat
output signal file
.TP
\fInew-record\fR.hea
output header file
.SH SEE ALSO
\fBsetwfdb\fR(1), \fBxform\fR(1), \fBheader\fR(5)
.SH AUTHOR
George B. Moody (george@mit.edu)
.SH SOURCE
http://www.physionet.org/physiotools/wfdb/app/snip.c
